[sb2] Add support for posix_spawn(). Fixes JB#49495

scratchbox2/execs/sb_exec.c

@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2006,2007 Lauri Leukkunen <lle@rahina.org>
+ * Copyright (C) 2020 Open Mobile Platform LLC.
  *
  * Licensed under LGPL version 2.1
  */
@@ -11,7 +12,8 @@
  * Brief description of the algorithm follows:
  * 
  * 0. When an application wants to execute another program, it makes a call
- *    to one of execl(), execle(), execlp(), execv(), execve() or execvp().
+ *    to one of execl(), execle(), execlp(), execv(), execve(), execvp() or
+ *    posix_spawn().
  *    That call will be handled by one of the gate functions in 
  *    preload/libsb2.c. Eventually, the gate function will call "do_exec()"
  *    from this file; do_exec() calls prepare_exec() and that is the place
@@ -1765,6 +1767,92 @@ int do_exec(int *result_errno_ptr,
 	return(result);
 }
 
+int do_posix_spawn(int *result_errno_ptr,
+	const char *exec_fn_name, pid_t *pid, const char *orig_path,
+    const posix_spawn_file_actions_t *file_actions,
+    const posix_spawnattr_t *attrp,
+	char *const *orig_argv, char *const *orig_envp)
+{
+	char *new_path = NULL;
+	char **new_argv = NULL;
+	char **new_envp = NULL;
+	int  result;
+	PROCESSCLOCK(clk1)
+
+	START_PROCESSCLOCK(SB_LOGLEVEL_INFO, &clk1, "do_posix_spawn");
+	if (getenv("SBOX_DISABLE_MAPPING")) {
+		/* just run it, don't worry, be happy! */
+	} else {
+		int	r;
+		char	**my_envp_copy = NULL; /* used only for debug log */
+		char	*tmp, *binaryname;
+		enum binary_type type;
+
+		tmp = strdup(orig_path);
+		binaryname = strdup(basename(tmp)); /* basename may modify *tmp */
+		free(tmp);
+
+		if (SB_LOG_IS_ACTIVE(SB_LOGLEVEL_DEBUG)) {
+			char *buf = strvec_to_string(orig_argv);
+
+			SB_LOG(SB_LOGLEVEL_DEBUG,
+				"SPAWN/Orig.args: %s : %s", orig_path, buf);
+			free(buf);
+
+			/* create a copy of intended environment for logging,
+			 * before preprocessing */
+			my_envp_copy = prepare_envp_for_do_exec(orig_path,
+				binaryname, orig_envp);
+		}
+
+		new_envp = prepare_envp_for_do_exec(orig_path, binaryname, orig_envp);
+
+		r = prepare_exec(exec_fn_name, NULL/*exec_policy_name: not yet known*/,
+			orig_path, 0, orig_argv, orig_envp,
+			&type, &new_path, &new_argv, &new_envp);
+
+		if (SB_LOG_IS_ACTIVE(SB_LOGLEVEL_DEBUG)) {
+			int saved_errno = errno;
+			/* find out and log if preprocessing did something */
+			compare_and_log_strvec_changes("argv", orig_argv, new_argv);
+			compare_and_log_strvec_changes("envp", my_envp_copy, new_envp);
+			errno = saved_errno;
+		}
+
+		if (r < 0) {
+			*result_errno_ptr = errno;
+			SB_LOG(SB_LOGLEVEL_DEBUG,
+				"EXEC denied by prepare_exec(), %s", orig_path);
+			STOP_AND_REPORT_PROCESSCLOCK(SB_LOGLEVEL_INFO, &clk1, "Exec denied");
+			return(r); /* exec denied */
+		}
+
+		if (check_envp_has_ld_preload_and_ld_library_path(
+			new_envp ? new_envp : orig_envp) == 0) {
+
+			SB_LOG(SB_LOGLEVEL_ERROR,
+				"exec(%s) failed, internal configuration error: "
+				"LD_LIBRARY_PATH and/or LD_PRELOAD were not set "
+				"by exec mapping logic", orig_path);
+			*result_errno_ptr = EINVAL;
+			STOP_AND_REPORT_PROCESSCLOCK(SB_LOGLEVEL_INFO, &clk1, "Config error");
+			return(-1);
+		}
+	}
+
+	errno = *result_errno_ptr; /* restore to orig.value */
+	STOP_AND_REPORT_PROCESSCLOCK(SB_LOGLEVEL_INFO, &clk1, orig_file);
+	result = sb_next_posix_spawn(pid,
+		(new_path ? new_path : orig_path),
+        file_actions, attrp,
+		(new_argv ? new_argv : orig_argv),
+		(new_envp ? new_envp : orig_envp));
+	*result_errno_ptr = errno;
+	SB_LOG(SB_LOGLEVEL_DEBUG,
+		"EXEC failed (%s), errno=%d", orig_path, *result_errno_ptr);
+	return(result);
+}
+
 /* ----- EXPORTED from interface.master: ----- */
 int sb2show__execve_mods__(
 	char *file,

scratchbox2/include/sb2.h

@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2006,2007 Lauri Leukkunen <lle@rahina.org>
+ * Copyright (C) 2020 Open Mobile Platform LLC.
  *
  * Licensed under LGPL version 2.1, see top level LICENSE file for details.
  */
@@ -28,6 +29,8 @@
 #include <dmalloc.h>
 #endif
 
+#include <spawn.h>
+
 /* "sb2context" used to be called "lua_instance", but
  * was renamed because it is now used for other purposes,
  * too, and can even be used without activating Lua system
@@ -189,6 +192,17 @@ extern int sb_next_execve(const char *filename, char *const argv [],
 extern int do_exec(int *result_errno_ptr, const char *exec_fn_name, const char *file,
 		char *const *argv, char *const *envp);
 
+extern int sb_next_posix_spawn(pid_t* pid, const char *path,
+        const posix_spawn_file_actions_t *file_actions,
+        const posix_spawnattr_t *attrp, char *const argv [],
+        char *const envp[]);
+
+extern int do_posix_spawn(int *result_errno_ptr,
+        const char *exec_fn_name, pid_t *pid, const char *orig_path,
+        const posix_spawn_file_actions_t *file_actions,
+        const posix_spawnattr_t *attrp,
+        char *const *orig_argv, char *const *orig_envp);
+
 extern time_t get_sb2_timestamp(void);
 
 extern char *procfs_mapping_request(const char *path);

scratchbox2/preload/execgates.c

@@ -3,6 +3,7 @@
  * 		(also contains GATEs for the setrlimit() functions)
  *
  * Copyright (C) 2006,2007 Lauri Leukkunen <lle@rahina.org>
+ * Copyright (C) 2020 Open Mobile Platform LLC.
  * parts contributed by 
  * 	Riku Voipio <riku.voipio@movial.com>
  *	Toni Timonen <toni.timonen@movial.com>
@@ -124,6 +125,75 @@ int sb_next_execve(const char *file, char *const *argv, char *const *envp)
 	return next_execve(file, argv, envp);
 }
 
+static int (*next_posix_spawn) (pid_t* pid, const char *path,
+        const posix_spawn_file_actions_t *file_actions,
+        const posix_spawnattr_t *attrp, char *const argv [],
+        char *const envp[]) = NULL;
+
+int sb_next_posix_spawn(pid_t* pid, const char *path,
+        const posix_spawn_file_actions_t *file_actions,
+        const posix_spawnattr_t *attrp, char *const argv [],
+        char *const envp[])
+{
+	if (next_posix_spawn == NULL) {
+		next_posix_spawn = sbox_find_next_symbol(1, "posix_spawn");
+	}
+
+	if (SB_LOG_IS_ACTIVE(SB_LOGLEVEL_DEBUG)) {
+		char *buf = strvec_to_string(argv);
+
+		if (buf) {
+			SB_LOG(SB_LOGLEVEL_DEBUG, "EXEC: file:%s argv:%s", path, buf);
+			free(buf);
+		} else {
+			SB_LOG(SB_LOGLEVEL_DEBUG,
+				"EXEC: %s (failed to print argv)", path);
+		}
+	}
+	if (SB_LOG_IS_ACTIVE(SB_LOGLEVEL_NOISE)) {
+		char *buf = strvec_to_string(envp);
+
+		if (buf) {
+			SB_LOG(SB_LOGLEVEL_NOISE, "EXEC/env: %s", buf);
+			free(buf);
+		} else {
+			SB_LOG(SB_LOGLEVEL_NOISE,
+				"EXEC: (failed to print env)");
+		}
+	}
+
+	switch (restore_stack_before_exec) {
+	case 1:
+		SB_LOG(SB_LOGLEVEL_DEBUG, "EXEC: need to restore stack limit");
+
+		if (setrlimit(RLIMIT_STACK, &stack_limits_for_exec) < 0) {
+			SB_LOG(SB_LOGLEVEL_ERROR,
+				"setrlimit(stack) failed, "
+				"failed to restore limits before exec");
+		}
+		break;
+#ifndef __APPLE__
+	case 64:
+		SB_LOG(SB_LOGLEVEL_DEBUG, "EXEC: need to restore stack limit");
+
+		if (setrlimit64(RLIMIT_STACK, &stack_limits64_for_exec) < 0) {
+			SB_LOG(SB_LOGLEVEL_ERROR,
+				"setrlimit64(stack) failed, "
+				"failed to restore limits before exec");
+		}
+		break;
+#endif
+	}
+
+	/* NOTE: Following SB_LOG() call is used by the log
+	 *       postprocessor script "sb2-logz". Do not change
+	 *       without making a corresponding change to the script!
+	*/
+	SB_LOG(SB_LOGLEVEL_INFO, "EXEC: i_pid=%d path='%s'",
+		sb_log_initial_pid__, path);
+	return next_posix_spawn(pid, path, file_actions, attrp, argv, envp);
+}
+
 
 /* collect exec arguments from a varargs list to an array.
  * returns an allocated array (use free() to free it if exec fails)
@@ -442,6 +512,25 @@ int execvpe_gate(
 	return do_execvep(result_errno_ptr, realfnname, file, argv, envp);
 }
 
+int posix_spawn_gate(
+    int *result_errno_ptr,
+    int (*real_posix_spawn_ptr)(pid_t *pid, const char *path,
+        const posix_spawn_file_actions_t *file_actions,
+        const posix_spawnattr_t *attrp,
+        char *const argv[], char *const envp[]),
+	const char *realfnname,
+    pid_t *pid,
+    const char *path,
+    const posix_spawn_file_actions_t *file_actions,
+    const posix_spawnattr_t *attrp,
+    char *const argv[],
+    char *const envp[])
+{
+	(void)real_posix_spawn_ptr;
+    return do_posix_spawn(result_errno_ptr, realfnname, pid, path,
+        file_actions, attrp, argv, envp);
+}
+
 /* SETRLIMIT_ARG1_TYPE is defined in interface.master */
 
 int setrlimit_gate(

scratchbox2/preload/gen-interface.pl

@@ -3,6 +3,7 @@
 # gen-wrappers.pl -- an interface generator for scratchbox2 preload library
 #
 # Copyright (C) 2007 Lauri T. Aarnio
+# Copyright (C) 2020 Open Mobile Platform LLC.
 #
 #
 # This script is an interface generator for scratchbox 2. Based on
@@ -1018,6 +1019,7 @@ sub create_call_to_gate_fn {
 #include <string.h>
 #include <glob.h>
 #include <utime.h>
+#include <spawn.h>
 #ifdef HAVE_FTS_H
 #include <fts.h>
 #endif

scratchbox2/preload/interface.master

@@ -7,6 +7,7 @@
 -- see gen-interface.pl for details.
 --
 -- Copyright (C) 2007 Lauri T. Aarnio
+-- Copyright (C) 2020 Open Mobile Platform LLC.
 
 @MAN:	.SH NAME
 @MAN:	libsb2_interface, list of functions defined in the scratchbox2 preload library
@@ -110,6 +111,11 @@ GATE: int execve (const char *filename, char *const argv [], char *const envp[])
 GATE: int execvp (const char *file, char *const argv [])
 GATE: int execvpe(const char *file, char *const argv[], char *const envp[])
 
+GATE: int posix_spawn (pid_t *pid, const char *path, \
+                       const posix_spawn_file_actions_t *file_actions, \
+                       const posix_spawnattr_t *attrp, \
+                       char *const argv[], char *const envp[])
+
 GATE: char * getcwd (char *buf, size_t size) : \
 	returns_string create_nomap_nolog_version
 GATE: char *__getcwd_chk (char *buf, size_t size, size_t buflen) : \